Global emissions of refrigerants HCFC-22 and HFC-134a: Unforeseen seasonal contributions

  • 9 December 2014

CPO's AC4 program is acknowledged in a paper published in the Proceedings of the National Academy of Sciences. The paper "Global Emissions of Refrigerants HCFC-522 and HFC-134a: Unforeseen Seasonal Contributions" is about seasonality in emissions of these refrigerants on a global scale. The research, which was published in the Dec. 9 issue of PNAS, was a collaboration between NOAA and Harvard University scientists, among others.

HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. 

The researchers found pronounced seasonal variations of global emissions for these two major refrigerants, with summer emissions two to three times higher than in winter. Thus results suggest that global emissions of these potent greenhouse gases might be mitigated by improved design and engineering of refrigeration systems and/or by reinforcing system service regulations.

To view the full paper, visit:




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